In a typical catalytic cracking of heavy hydrocarbons containing metal such as nickel and vanadium, it is well known that the metal (e.g., vanadium) deposited on a catalyst breaks a crystalline structure of an active component (crystalline aluminosilicate (generally also referred to as zeolite) of the catalyst, leading to a significant decline in an activity of the catalyst. In order to solve this problem, various catalysts are proposed.
Patent Literature 1 discloses a catalyst for hydrocarbon catalytic cracking containing: (1) an alumina particle having a particle diameter of 2 to 60 μm and including a phosphorus component and at least one metallic component selected from an alkaline earth metal and a rare earth metal; (2) zeolite; and (3) a porous inorganic oxide matrix in which the alumina particle (1) and zeolite (2) are evenly dispersed. It is disclosed that this catalyst exhibits a metal tolerance, a high activity and selectivity and inhibits generation of hydrogen and coke.
Patent Literature 2 discloses a catalyst composition for fluid catalytic cracking of hydrocarbon, containing components of alumina, zeolite, and a matrix of an inorganic oxide other than alumina, each of the components containing a phosphorus atom. It is disclosed that, when this catalyst is used for heavy hydrocarbon catalytic cracking, the catalyst exhibits an excellent bottom (bottom oil) cracking ability, generate only a low amount of hydrogen and coke, and increases fractions of gasoline, kerosene and light oil.
Patent Literature 3 discloses a porous molecular sieve catalyst having hydrothermal stability, which is obtained by water evaporation of a feedstock mixture including: (1) a molecular sieve having a surface pore modified by a specific phosphate and having a skeleton of —Si—OH—Al—; (2) a water-insoluble metal salt; and (3) a phosphate compound. It is disclosed that this catalyst has a high hydrothermal tolerance and improves a gas-olefin yield and gas-olefin selectivity.
Patent Literature 4 discloses a manufacturing method of a catalyst for catalytic cracking including: spray-drying aqueous slurry in a form of a mixture including air-calcined alumina, clay including silica and alumina as main components, a precursor of a silica inorganic oxide, and zeolite to provide spherical microparticles; washing the microparticles so as to have a content of an alkali metal oxide at 1.0 mass % or less; and introducing rare earths into the microparticles. It is disclosed that, when this catalyst is used for catalytic cracking of heavy hydrocarbon oil containing a large amount of metal, this catalyst exhibits a high cracking activity and a high gasoline selectivity, generates coke and gas at a low amount, and further has a high hydrothermal tolerance.
Patent Literature 5 discloses a catalyst for fluid catalytic cracking of hydrocarbon oil, the catalyst containing two or more of catalyst compositions containing zeolite and an inorganic oxide matrix formed of an active matrix component and an inactive matrix component, in which each of the catalyst compositions contains zeolite at different amounts (including a case where one of the catalyst compositions contains no zeolite). It is disclosed that, when this catalyst is used, gasoline and an intermediate fraction can be obtained at a high yield while a yield of coke can be lowered, and further a high bottom cracking ability, in other words, a low yield of a heavy fraction can be achieved.
Patent Literature 6 discloses a catalyst for fluid catalytic cracking of hydrocarbon oil, the catalyst containing: a catalyst composition A containing zeolite and a silica binder of 10 to 30 mass % as a binding agent; and a catalyst composition B containing zeolite and an aluminum compound binder of 10 to 30 mass % as a binding agent, in which the catalyst composition A of a mass (WA) is blended with the catalyst composition B of a mass (WB) at any mass ratio (WA:WB) within a range of 10:90 to 90:10. It is disclosed that, when this catalyst is used, gasoline and a light oil fraction can be obtained at a high yield while a yield of coke can be lowered, and further a high bottom cracking ability can be achieved, in other words, generation of a heavy fraction can be inhibited.